Lower heart rate variability associated with military sexual trauma rape and posttraumatic stress disorder.

Low heart rate variability (HRV) can occur with psychological disorders such as posttraumatic stress disorder (PTSD). The purpose of this study was to examine the association between PTSD by trauma type and decreased HRV measures in female veterans with cardiac symptoms. This secondary analysis utilized data from a previous study of female veterans (n = 125) examined for cardiac symptoms by Holter and electrocardiogram recordings at a Veterans Affairs medical center. The mean HRV measure from three 10-s data segments with spontaneous respirations was obtained for each subject. PTSD diagnosis and type of trauma exposure were collected from mental health consult notes. Chi-square was used for frequency of subject characteristics; independent t tests and one-way analysis of variance (ANOVA) compared means of HRV measures between trauma types. Statistical significance was set at p < .05 a priori. By ANOVA, significantly lower log-transformed standard deviation of all normal sinus rhythm R-R intervals (SDNN) and log-transformed square root of the mean of the sum of the squares of differences between adjacent normal sinus rhythm R-R intervals (RMSSD) were found in the PTSD group with documented rape military sexual trauma (MST) compared to other groups including no PTSD, PTSD following MST with rape not specified, combat exposure, and nonmilitary-related trauma; lower HRV measures were not found with other PTSD types of trauma. This study suggests rape MST with concomitant PTSD may be a risk factor for decreased HRV in female veterans examined for cardiac symptoms.